Submit Interaction not working

Hi,

I have a project with 4 stages (SL3).

every stage is formed from 3 slides- overall 12 slides.

every stage has 2 slides in which interaction and results are submitted, however, some of the slides simply don't submit the interaction.

for example, in the file attached, the first 3 slides work perfectly, the 6th slide doesn't report any interaction.

I tried counting the amount of triggers and compare it to another slide which is identical to that one (1st slide), tried overwriting the slide submit interaction and submit results triggers, still not working. 

tried checking the form view, if it has any sort of problem- nada.

Can anyone take a look?

I'm talking about the 6th slide in the example attached.

 

thanks,

Bar